"""Tests for async_utils."""

from __future__ import annotations

import asyncio
import time
from concurrent.futures import ThreadPoolExecutor

from app.utils.async_utils import run_blocking


async def test_run_blocking_executes_callable_in_thread() -> None:
    """run_blocking should execute the provided callable and return its result."""

    def blocking_add(x: int, y: int) -> int:
        return x + y

    result = await run_blocking(blocking_add, 3, 4)
    assert result == 7


async def test_run_blocking_accepts_custom_executor() -> None:
    """run_blocking should use a provided executor when one is passed."""

    def blocking_value() -> str:
        return "ok"

    executor = ThreadPoolExecutor(max_workers=1)
    try:
        result = await run_blocking(blocking_value, executor=executor)
        assert result == "ok"
    finally:
        executor.shutdown(wait=True)


async def test_run_blocking_does_not_block_event_loop() -> None:
    """A blocking callable should not stall other async tasks."""

    def sleep_block() -> str:
        time.sleep(0.05)
        return "done"

    task = asyncio.create_task(run_blocking(sleep_block))
    # Yield control to ensure the event loop can run other tasks while the
    # blocking work executes in the thread pool.
    await asyncio.sleep(0)
    result = await task
    assert result == "done"